Method and apparatus for forming longitudinal corrugations in sheet material



April 13, 1965 L. E. TISDALE 3,178,494

METHOD AND APPARATUS FOR FORMING LONGITUDINAL CORRUGATIONS IN SHEET MATERIAL Filed Nov. 15, 1962 3 Sheets-Sheet 1 WW a Fig.

Lucien E. 7 'isda/e IN VEN TOR.

April 13, 1965 3,178,494

METHOD AN AL L. E. TlSDALE D APPARATUS FOR FORMING LONGITUDIN COR IIONS IN SHEET MATERIAL Filed Nov. 15, 1962 5 Sheets-Sheet 2 Fig. 24

Lucien E Tisdale 1 N VEN TOR I l l l l l l I Aprll 13, 1965 E. TISDALE 3,178,494

METHOD AND APPARATUS FOR FORMING LONGITUDINAL CORRUGATIONS IN SHEET MATERIAL Filed Nov. 15, 1962 3 Sheets-Sheet 3 Lucian E Tisdale 1 N VEN TOR.

BY WWW km.

United States Patent METHOD AND APPARATUS FUR FGRMHNG LONGETUDENAL (JGRRUGATIUNS DI SHEET MATERIAL Lucien E. Tisdale, Bastrop, La. (3512 Forsythe Ave., Monroe, La.) Filed Nov. 1962, Ser. No. 237,836 12 Claims. (Cl. 264-436) This invention relates to a novel and useful method and apparatus for forming longitudinal corrugations in sheet material.

The apparatus of the instant invention provides a means whereby longitudinal corrugations may be formed in a paper web which is to be used in the manufacturing of corrugated board for boxes and shipping containers. The paper web is drawn from a paper roll and as the Web moves through the apparatus it is first steamed by means of steam spray heads and is then acted upon by laterally spaced longitudinal lines of force from opposite sides of the web and with the lines of force applied to one side of the web being staggered relative to the lines of force applied to the other side of the web and the lines of force on each side of the web being convergent toward the direction of travel of the web.

While numerous types of apparatus have heretofore been designed for applying these staggered longitudinal and convergent lines of force to opposite sides of a sheet of material which is to have longitudinal corrugations formed therein, most of these prior apparatus have involved either elaborate grooved opposing conveyor belts which may be stretched transversely or a plurality of narrow belts disposed in opposing courses of belts and with the belts of each course being staggered relative to each other, or apparatus which utilize various other complicated forms of machinery to gradually transversely shrink an elongated sheet of material in order to form corrugations therein.

While most of the above mentioned different types of apparatus function well to form corrugations in sheet material, they are usually most elaborate and thus very expensive to manufacture and to upkeep.

It is therefore the main object of this invention to provide an improved apparatus and an improved method for forming longitudinal corrugations in sheet material.

A further object of this invention, in accordance with the preceding object, is to provide an apparatus and method which will enable corrugations to be more permanently formed in a paper web.

Still another object of this invention is to provide an apparatus and method for continuously corrugating material in web or strip form in such a manner that the web may be corrugated with a minimum of danger of the web being torn during the formation of corrugations therein.

Still another object of this invention is to provide an apparatus and method for forming continuous longitudinal corrugations in sheet material which will enable the corrugations to be formed without the sheet material moving laterally of any surface with which it is in contact.

A final object of this invention to be specifically enumerated herein is to provide an apparatus and method for forming continuous longitudinal corrugations in sheet material which will vconform to conventional forms of manufacture, be of simple construction and easy to use so as to provide a device that will be economically feasible, long lasting and relatively trouble free in operation.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as'more fully hereinafter described and claimed, reference being had to the accom- "ice panying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURES l and 1a are top plan views of different halves of the machine of the instant invention;

FIGURES 2 and 2a are side elevational views of different halves of the machine illustrated in FIGURES 1 and 1a;

FIGURE 3 is an enlarged fragmentary transverse vertical sectional view taken substantially upon the plane indicated by the section line 3-3 of FIGURE 1;

FIGURE 4 is an enlarged fragmentary transverse vertical sectional view taken substantially upon the plane indicated by the section line 44 of FIGURE 1; and

FIGURE 5 is an enlarged transverse fragmentary vertical sectional view taken substantially upon the plane indicated by the section line 5-5 of FIGURE 1a.

Referring now more specifically to the drawings the numeral 10 generally designates the apparatus of the instant invention. The apparatus 10 comprises a machine including elongated support means generally referred to by the reference numeral 12. The elongated support means 12 includes an elongated support member generally referred to by the reference numeral 14 whichcomprises a vacuum manifold generally referred to by the reference numeral 16 over which the upper reach 18 of an endless conveyor assembly generally referred to by the reference numeral 20 is disposed. The conveyor assembly 2.1) includes an inlet end 22 and an outlet end 24. A multi-grooved roller 26 is rotatably supported at the inlet end 22 and a second multi-grooved roller 28 is rotatably supported at the outlet end 24. A plurality of endless flexible members 30 which are generally circular in cross section and can comprise substantially any type of generally cylindrical and endless flexible members are entrained over the rollers 26 and 28. The vacuum manifold 16 includes a top wall 32 which has a plurality of longitudinally extending rows of spaced openings 34 formed therethrough. The rows of openings 34 are convergent toward the outlet end 24 of the support member 14 and a plurality of longitudinally extending and. upstanding guide members 36. are secured to and project upwardly from the top wall 32 between adjacent ones of the rows of openings 34. The upstanding guide members 36 include semi-cylindrical upwardly opening upper surfaces 38 and the endless flexible members 36 are cradled in and guided by the semi-cylindrical surfaces 38 during their movement over the vacuum manifold 16. The vacuum manifold 16 is communicated with a vacuum header 40 by means of branch conduits 42 having valves.44 disposed therein. It is to be understood that the vacuum header may be connected to any suitable source of vacuum.

A pair of steam head pipes 48 and 5t) are disposed at the inlet end 22 of the support member 14 and generally parallel each other. The steam head pipes 50 and 48 are each provided with a plurality of steam outlet nozzles 52 and it may be seen that the elongated web 54 which is being unrolled from the roll 56 is rotatably supported at the inlet end 22 of the support member 14 by means of journal stands 58, passes between the steam head pipes 48 and St; and may have steam sprayed thereon before the web 54 passes upwardly over the roller 26 and moves into overlying relation with the vacuum manifold 16.

The inlet end of the vacuum manifold 16 is provided with a seal 60 and the outlet end of the vacuum manifold 16 is provided with a seal 62. The seals Band 62 are secured to the end walls 64 and 66 of the vacuum mani fold 16 and form a seal between the vacuum manifold 16 and the undersurface of the web 54 in order to close the opposite ends of the upwardly opening grooves 68 formed between adjacent ones of the ridges defined by the endless flexible members 30.

The roller 28 has a driven pulley 70 mounted thereon 2 u and the driven pulley 70 is driven by means of an endless flexible belt 72 which is entrained thereover and also over a drive pulley 74 of a gear reduction assembly 76 whose input shaft has an electric motor 78 drivingly connected thereto.

The machine also includes an elongated support member generally referred to by the reference numeral 80. The elongated support member 30 comprises a vacuum manifold generally referred to by the reference numeral 82 which is similar to the vacuum manifold 16 except that the upper surface of the top wall 84 thereof is planar. The support member 80 includes a conveyor assembly generally referred to by the reference numeral 84 which is similar to the conveyor assembly except that it includes a pair of smooth rollers 86 and 88 over which a single endless flexible belt 90 is entrained. The endless flexible belt 90 includes a plurality of longitudinally extending and transversely spaced parallel ridges 92 which define therebetween a plurality of upwardly opening grooves 94. The belt 90 has a plurality of openings 96 formed therethrough which open upwardly through the bottoms of the grooves 94. The openings 96 formed through the belt 90 are registrable with the rows of openings 98 formed through the top wall 100 of the vacuum manifold 82.

As was the case with the vacuum manifold 16, the interior of the vacuum manifold 82 is communicated with a vacuum header 104 by means of branch conduits 106 having control valves 108 disposed therein.

However, a heating and drying assembly generally referred to by the reference numeral 116 is provided for the support member 80 and overlies the vacuum manifold 82 in spaced relation relative to the upper reach 118 of the belt 90. The heating and drying assembly 116 may be of any conventional type utilizing forced hot air and therefore it is to include a heating assembly and blower means (not shown) for directing heated air over the upper surface of the portion of the web 54 disposed over the vacuum manifold 82.

The roller 88 has a driven pulley 120 mounted thereon which is drivingly connected to a driven pulley 122 by means of an endless flexible belt 124. The driven pulley 122 is mounted on an output shaft 126 of a gear reduction assembly 128 and an electric motor 130 is drivingly connected to the input shaft 132 of the gear reduction assembly 128.

It is to be noted that the conveyor assemblies 20 and 84 will be operated at the same speed and that the web 54 will move from one conveyor assembly 20 directly onto the other conveyor assembly 84.

In operation, as the web 54 is unrolled from the roll 56, it passes between the steam head pipes 48 and 50 at which time steam is directed upon the opposite surfaces of the web 54 in order to heat and soak the web 54. After the web 54 has been heated and soaked by means of the steam, it may be more readily corrugated without tearing the fibers from which the Web is constructed.

As the web 54 passes over the seal 60, the seal 60 seals the ends of the grooves 68 on the inlet end of the grooves 68 on the inlet end of the vacuum manifold 16. Then, as the undersurface of the web 54 is supported by the upper surfaces of the elongated flexible members 39 and the latter apply longitudinally extending and convergent lines of force to the undersurface of the web 54, the reduction in air pressure within the grooves 68 will of course cause a pressure differential to exist on opposite slides of the web 54 and therefore generally parallel and longitudinally extending areas of force to be directed downwardly upon the upper surface of the web 54 along lines staggered relative to the upward lines of force applied by the elongated flexible members 30. Accordingly, as the endless flexible members 30 are convergent toward the outlet end 24 of the conveyor assembly 20 in the upper reach 18 thereof, the corrugations 134 are slowly formed in the web 54 as the web is gradua ly reduced in width. Inasmuch as the web 54 has been thoroughly heated and wetted prior to the formation of the corrugations 134 therein, the fibers of the material from which the web 54 has been formed will not be torn apart or broken. Then, after the corrugations have been formed as shown in FIGURE 4 of the drawings, the web 54 passes from the conveyor assembly 20 and onto the conveyor assembly 84 whereupon the corrugations 134 are maintained in the web 54 by means of the ribbed or ridged belt $0 while heated air is directed over the upper surfaces of the web 54 to effect its drying. In addition, the reduction in pressure along the undersurfaces of the portion of the web 54 supported by the vacuum manifold 82 will cause some of the heated air from the assembly 116 to pass through the fibrous web 54 and to therefore more quickly dry the latter.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. A machine for forming longitudinal corrugations in sheet material, said machine comprising elongated support means for receiving and carrying said sheet material, said support means including inlet and outlet ends and defining a plurality of generally parallel longitudinally extending ridges which in turn define a plurality of longitudinally extending and upwardly opening grooves therebetween, said ridges being convergent toward the outlet end of said support, means communicating said grooves with a source of vacuum, said elongated support means comprising an endless conveyor with said ridges being defined by corresponding coplanar reaches of a plurality of endless flexible members guided for straight line movement between the inlet and outlet ends of said conveyor.

2. The combination of claim 1 wherein at least the inlet end of said support includes seal means disposed in registry with the adjacent ends of said grooves and adapted to engage a sheet of material supported from said ridges and to thereby close said adjacent ends of said grooves.

3. The combination of claim 1 wherein said machine includes means on the inlet end portion thereof for wetting sheet material prior to completion of its passage along said ridges.

4. The combination of claim 1 wherein said machine includes an elongated support member having an inlet end aligned with the outlet end of said support means and also defining a plurality of generally parallel longitudinally extending ridges which in turn define a plurality of upwardly opening and longitudinally extending grooves therebetween, said ridges of said support member being registered with the outlet ends of the ridges of said support means for receiving a corrugated sheet therefrom, means communicating said support member grooves with a source of vacuum and heating means supported above said support member ridges for drying the corrugated sheet passing along said last-mentioned ridges.

5. The combination of claim 5 wherein said outlet end of said support means includes seal means disposed in registry with the adjacent ends of the corresponding grooves and adapted to engage a sheet of material supported from said last-mentioned ridges, and to thereby close said last-mentioned corresponding grooves.

6. The combination of claim 1 wherein said heating means includes forced hot air drying means.

7. The combination of claim 1 wherein said support means includes an elongated support along which a portion of said flexible members are slidingly supported, said elongated support comprising one wall of a vacuum manifold comprising said source of vacuum, a plurality of openings formed through said elongated support.

8. The combination of claim 7 wherein said elongated support includes a plurality of longitudinally extending and upstanding guide members secured thereto, converging toward the outlet end of said elongated support means, said upstanding guide members including semicylindrical upwardly opening upper surfaces, said endless flexi ble members being generally circular in cross section and cradled by said semi-cylindrical surfaces.

9. A machine for forming longitudinal corrugations in sheet material, said machine comprising elongated support means for receiving and carrying said sheet material, said support means including inlet and outlet ends and defining a plurality of continuous generally parallel longitudinally extending ridges adapted for fluid sealing engagement with one side of said sheet and defining a plurality of longitudinally extending and upwardly opening grooves therebetween, said ridges being convergent toward the outlet end of said support, said support means being supported from said machine for simultaneous straight line longitudinal movement from the inlet end of said support means to the outlet end thereof, and means communicating said grooves with a source of vacuum.

10. A method of forming continuous longitudinal corrugations in an elongated sheet of flexible deformable material comprising the following steps: longitudinally moving said sheet over support means defining a plurality of generally parallel elongated members convergent toward one set of corresponding ends, being longitudinally advanced toward said one set of corresponding ends at a speed equal to the longitudinal speed of said sheet, and defining a plurality of grooves extending longitudinally of and disposed between said members and opening toward the adjacent side of said sheet with said flexible sheet disposed in contacting fluid sealing engagement with said members while simultaneously reducing the air pressure in said grooves.

11. The method of claim 10 including the step of dampening said sheet material prior to completion of its passage over said support means.

12. The method of claim 10 including the step of drying said sheet material while simultaneously retaining the corrugations therein.

References Cited by the Examiner UNITED STATES PATENTS Re. 23,910 12/54 Smith et al 18-19 654,884 7/00 Ferres 156-462 1,784,906 12/30 Oxhandler 18-56 2,084,362 6/37 Visscher et a1 156-142 2,166,749 7/39 Burrill 156-471 2,314,757 3/43 Benedict 156-462 2,586,481 2/52 Rooksby et al. 18-56 2,876,824 3/59 West et al. 156-342 3,024,496 3/62 Colombo 18-19 3,102,776 9/63 Steinmann et al. 18-56 ALEXANDER H. BRODMERKEL, Primary Examiner. 

9. A MACHINE FOR FORMING LONGITUDINAL CORRUGATIONS IN SHEET MATERIAL, SAID MACHINE COMPRISING ELONGATED SUPPORT MEANS FOR RECEIVING AND CARRYING SAID SHEET MATERIAL, SAID SUPPORT MEANS INCLUDING INLET AND OUTLET ENDS AND DEFINING A PLURALITY OF CONTINUOUS GENRALLY PARALLEL LONGITUDINALLY EXTENDING RIDGES ADAPTED FOR FLUID SEALING ENGAGEMENT WITH ONE SIDE OF SAID SHEET AND DEFINING A PLURALITY OF LINGITUDINALLY EXTENDING AND UPWARDLY OPENING GROOVES THEREBETWEEN, SAID RIDGES BEING CONVERGENT TOWARD THE OUTLET END OF SAID SUPPORT, SAID SUPPORT MEANS BEING SUPPORTED FROM SAID MACHINE FOR SIMULTANEOUS STRAIGHT 